In London, Foreign Secretary David Miliband summoned the Sudanese Ambassador, while Downing Street made it clear that Gordon Brown was 'disappointed' over the 54-year-old teacher being charged.

The Muslim Council of Britain said it was "appalled" at the decision.

Legal sources in Khartoum said it is possible the case could be dealt with in a single hearing.

One lawyer said that if Mrs Gibbons pleads guilty and makes profuse apologies, she could emerge with a "relatively minor penalty" such as a hefty fine or a jail term equivalent to the four days she has already spent in custody.

Mrs Gibbons, a former deputy head in Liverpool, moved to Khartoum in August to fulfil her dream of teaching abroad after her marriage broke down last year.

The mother of two grown-up children was arrested on Sunday after parents were said to have complained she had insulted Islam's prophet by naming a teddy bear Mohammed as part of a class project.

However, a boy of seven came forward on Tuesday to say it was "all his fault", as he and his classmates at the Unity High School had voted to call the bear Mohammed after his own name.

He insisted his teacher had not intended to insult Islam.

Mrs Gibbons technically faces three charges - insulting Islam, inciting religious hatred and contempt for religious beliefs - each of which carries a maximum penalty of 40 lashes and a year in jail. But it is believed she will stand trial on only one.

Abdul Daem Zumrawi, the Justice Ministry's undersecretary, said: "What will be applied is at the discretionary power of the judge."

Mrs Gibbons's former husband, Peter Gibbons, 54, said last night that he and their children Jessica, 27, and John, 25, had been horrified at the news that she had been charged.

What's interesting is that while a few of the commenters [at the BBC site] who say they're Muslims are condemning Mrs Gibbons, or falling back on the 'Western foreign policy' excuse, the majority are either suggesting that she made a simple mistake, and should be treated leniently, or are condemning the Sudanese outright – "Stop hijacking the religion!" pleads Adil in Singapore.By contrast, virtually all of the comments attacking Mrs Gibbons, and making excuses for Islamic extremism, are from people living in Britain, with a few from the US and elsewhere in Europe, and who, judging by their names – Louise, Graeme, Mike, Mary, Suzanne, George – are natives of those countries, and very probably white.